Most prosthetic feet are configured so that the angle formed between the foot and a prosthetic leg joined thereto is fixed. As a consequence, the heel height cannot be varied, and this can present problems when a user switches from one style of shoe to another. The limitations of the fixed angle also prevent a user from dropping or relaxing his or her foot when sitting.
As a consequence, it will be appreciated that there is a need for a prosthetic foot wherein the angle between the foot and the pylon of a prosthetic leg may be user adjustable. Any such adjustment mechanism should be easy and quick to make, and reliable. Also, since prosthetic feet are subjected to high mechanical loadings, any such adjustment mechanism should be sturdy. The prior art has implemented a number of approaches to providing for heel height adjustment in prosthetic feet. These approaches include hydraulic, mechanical and electromechanical devices. In general, prior art adjustment mechanisms have been found to be relatively complicated which can make them expensive and difficult to use.
As will be explained in detail hereinbelow, the present invention provides a heel height adjustment system for prosthetic feet, which system is simple in its construction, reliable, sturdy, easy to use, and capable of providing a fine degree of control over the range of adjustments. In addition, the system of the present invention may be activated by a control which is remote from the foot so as to facilitate adjustments while the foot is in use. These and other advantages of the invention will be explained in detail hereinbelow.